Excessive cholesterol (hyperlipoproteinemia) in the body leads to sclerosis (arteriosclerotic plaque) of the interior layers of the blood vessels, and to a gradual hardening and thickening of the arterial walls. In an extreme case, it threatens blocking of the vessels, or in the event of rupture of the plaque, thrombus formation. Arteriosclerosis with its secondary illnesses (coronary illnesses, heart attacks, peripheral arterial diseases and strokes) is still the most frequent cause of death in the western world. Well over half of all the financial resources available for medical care are estimated to be spent for the consequences of arteriosclerosis. To clarify the causes of arteriosclerosis, various theories have been developed, of which the lipid theory is the most highly regarded.
In general, it can be stated that the higher the LDL cholesterol level or level of oxidized LDL cholesterol in the blood, the high the risk of vascular hardening, for example with the consequence of a heart attack. Overweight and hypercholesterolemia are the most important risk factors for the development of arteriosclerosis.